Another approach is the more classic 3-stager, using Shapelock to mould the outer ear, which is then machined to fit the plug. It's hard, though, so form a negative mould from the old-style mix of talc avd silicove, avd finally go for the final mould in Sugru from that. It also gives you several goes from one moulding

Don't forget a lot of the firearm sound is percussive blast rather than true sound, so it also travels along bone, circumventing the plugs, which may even make it worse. This is why we use softer foam.

As a member of the International Guild of Knot Tyers, I'd recommend unlaying that rope being careful not to release the twist in each chord - just lift it away. That way you can lay it back together again so the metal's buried in the centre of the rope.

JFDI as told. What you wear under the pack frame is up to you, the torsion on the frame from that weight and distance may be considerable, and break spine spurs if carried directly on the bones as a corset does, causing permanent disaility.

Stitching or contact cement - or both

Seven Archangels, Michael, Raphael, Gabriel, Uriel, Saraqael, Raguel, and RemielAdd a tensor stop within the wing an inch or so below one hinge to limit it's spread. All you need is to screw a short piece of elastic to limit the throw, or wire and a catch.